A wide variety of electrochemical sensors (i.e., sensors employing an electrolytic cell with an anode, cathode and electrolyte) have been developed and employed for detecting and measuring the presence of various chemical compounds, in a sample.
U.S. Pat. Nos. 2,830,945, 4,800,000, 4,842,709 and 5,199,295 each disclose an electrochemical sensor for detecting and measuring water-vapor employing phosphoric acid as the electrolyte. However, the construction and design of these sensors severely limited the accuracy, sensitivity, responsiveness and service life of these sensors.
A strong need exists in certain industry segments for a cost-effective sensor capable of quickly and accurately detecting and measuring the water-vapor content of a sample to concentrations as low as a few parts per billion (ppb). Unfortunately, the currently available sensors, including those described in the patents referenced above, do not meet these requirements.
Accordingly, a strong need continues to exits for a cost-effective sensor capable of quickly and accurately measuring the water-vapor content of a sample to concentrations as low as a few ppb.